Webinar to examine stray shale-gas migration into groundwater

Webinar to examine stray shale-gas migration into groundwater

UNIVERSITY PARK, Pa. -- Investigations into natural gas from shale development migrating into groundwater will be the focus of a free, Web-based seminar offered by Penn State Extension.

To be presented at 1 p.m. on March 21, "A Geochemical Context for Stray Gas Investigations in the Northern Appalachian Basin," is part of a monthly series of one-hour webinars.

According to presenter Fred Baldassare, senior geoscientist with ECHELON Applied Geoscience Consulting, as shale gas exploration and development has increased over the past five years, stray gas migration in groundwater has become a hot topic. He will discuss the various sources of methane and the need to review each case individually to determine its origin.

"The occurrence of methane in aquifer systems represents a natural condition in many areas of the Appalachian Basin," he said. "The origin can be the result of microbial and thermogenic processes that convert organic matter in the aquifer strata to methane, and to lower concentrations of ethane and heavier hydrocarbons in some areas of the basin.

"Or it can result from the progressive migration of hydrocarbon gas over geologic time from the source and/or reservoir to the aquifer."

But in some instances, Baldassare pointed out, the stray gas that occurs in the aquifer and manifests in private water supplies can be the result of gas-well drilling.

"That happens where pressure combines with ineffective casing cement bonds to create pathways," he said. "Alleged incidents of stray gas migration must be investigated at the site-specific level and must include isotope geochemistry to determine gas origin and diagnostic evidence to determine a mechanism of migration."

Presented by Penn State Extension's Marcellus Education Team, the monthly natural-gas webinars usually are offered from 1 p.m. to 2 p.m. on Thursdays. Upcoming webinars will cover the following topics:

--April 24: Utica Reservoirs -- Mike Arthur, Penn State professor of geosciences and co-director of the Penn State Marcellus Center for Outreach and Research.

Previous webinars, publications and information also are available on the Penn State Extension natural-gas website (http://extension.psu.edu/naturalgas), covering a variety of topics, such as Act 13; seismic testing; air pollution from gas development; water use and quality; zoning; gas-leasing considerations for landowners; gas pipelines and right-of-way issues; legal issues surrounding gas development; and the impact of Marcellus gas development on forestland.

Registration for this webinar is not necessary, and all are welcome to participate by logging in to https://meeting.psu.edu/pscems . For more information, contact Carol Loveland at 570-320-4429 or by email at cal24@psu.edu .